
Symptom:
P-0133 1/1 O2S SLOW RESPONSE
When Monitored and Set Condition:
P-0133 1/1 O2S SLOW RESPONSE
When Monitored: With engine temperature greater than 63 degrees C (147 degrees F),
after reaching vehicle speed of 16 kmh (10 mph), and throttle remaining open (off idle), for
2 minutes bring vehicle to a stop and allow engine to idle with transmission in drive (auto)
or in neutral (manual).
Set Condition: The Oxygen Sensor Signal voltage is switching from below 0.27 volt to
above 0.62 volt and back fewer times than required.
POSSIBLE CAUSES
ENGINE MECHANICAL PROBLEM
1/1 O2 SENSOR GROUND CKT HIGH RESISTANCE
1/1 O2 SENSOR GROUND CKT POOR CONNECTION
1/1 O2 SENSOR SIGNAL CKT HIGH RESISTANCE
1/1 O2 SENSOR SIGNAL CKT POOR CONNECTION
1/1 O2 SENSOR SLOW RESPONSE
EXHAUST LEAK
1/1 O2S SLOW RESPONSE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1 With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 5
No®Go To 2
2 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Sensor Ground) Circuit between O2S Connector
(Sensor Ground) and PCM Connector (Sensor Ground).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 3
No®Repair poor connection (high resistance) on O2 Sensor Ground
Circuit.
Perform VERIFICATION TEST VER-5A3.
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TEST ACTION APPLICABILITY
3 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Signal) Circuit between O2S Connector (O2S
Signal) and PCM Connector (O2S Signal).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 4
No®Repair poor connection (high resistance) on O2S Signal Circuit.
Perform VERIFICATION TEST VER-5A3.
4 At this time the 1/1 O2S SLOW RESPONSE does not exist or is an intermittent
problem.
With the DRB, read the FREEZE FRAME DATA.
With this screen, attempt to duplicate the condition that has set this fault.
While using FREEZE FRAME pay particular attention to the fault setting condi-
tions, such as speed, temp, load, and map vacuum.
Does the 1/1 O2S SLOW RESPONSE reoccur?All
Ye s®Go To 5
No®The 1/1 O2S SLOW RESPONSE no longer exists.
Perform VERIFICATION TEST VER-5A3.
5 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Start the Engine.
NOTE: Check the exhaust for excessive smoke caused by oil or coolant
consumption.
Is there an oil or coolant consumption condition present?All
Ye s®Repair engine mechanical as necessary and replace O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Go To 6
6 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Start the Engine.
Check the Exhaust System for leaks between the Engine and the catalyst.
Are there any leaks?All
Ye s®Repair or replace leaking Exhaust System as necessary.
Perform VERIFICATION TEST VER-5A3.
No®Go To 7
7 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Turn Ignition On (Engine Off).
Using a voltmeter, backprobe O2S (Signal) Circuit between O2S Connector (O2S
Signal) and PCM Connector (O2S Signal).
Is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 8
No®Repair poor connection (high resistance) on O2S Signal Circuit.
Perform VERIFICATION TEST VER-5A3.
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DRIVEABILITY
P-0133 1/1 O2S SLOW RESPONSE ÐContinued
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Symptom:
P-0135 O2S HEATER FAILURE
When Monitored and Set Condition:
P-0135 O2S HEATER FAILURE
When Monitored: With the ignition key off, after the engine cools down.
Set Condition: No sensor output signal is received when the PCM powers up the sensor
heater.
POSSIBLE CAUSES
1/1 O2 SENSOR CONNECTOR DAMAGED
1/1 O2 SENSOR GND CIRCUIT OPEN
ASD RELAY OUTPUT CIRCUIT OPEN
1/1 O2 SENSOR FAILURE
1/1 O2 SENSOR HEATER ELEMENT FAILURE
1/1 O2S HEATER FAILURE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1 With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 2
No®Go To 3
2 Turn Ignition On (Engine Off), wait three minutes.
With the DRB , monitor the O2 Sensor voltage for a few minutes until the voltage
stabilizes between .4 and .6 volts.
With the DRB, actuate the O2 Heater Test.
Monitor O2 voltage for up to two minutes.
Is the O2 Sensor voltage still between .4 and .6 volts?All
Ye s®Go To 4
No®Go To 3
3 At this time the 1/1 O2S HEATER FAILURE does not exist or is an intermittent
problem.
With the DRB, read the FREEZE FRAME DATA.
With this screen, attempt to duplicate the condition that has set this fault.
While using FREEZE FRAME DATA pay particular attention to the fault setting
conditions, such as speed, temp, load, and map vacuum.
Does the 1/1 O2S HEATER FAILURE reoccur?All
Ye s®Go To 4
No®1/1 O2S Heater failure no longer exists.
Perform VERIFICATION TEST VER-5A3.
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Symptom:
P-0137 1/2 O2 SENSOR VOLTAGE SHORTED TO GROUND
When Monitored and Set Condition:
P-0137 1/2 O2 SENSOR VOLTAGE SHORTED TO GROUND
When Monitored: With the ignition key off, after the O2 Sensor cools down; and after the
next key on provided that it is a cold start (coolant temperature less than 38 degrees C
(100.4 degrees F) and ambient temperature within 13.7 degrees C (7.2 degrees F) of coolant
temperature.
Set Condition: The Downstream O2 Sensor Signal voltage is below 0.156 volt prior to O2
Sensor Heater test (cool down period), and O2 voltage less than 0.156 volt after the key on
in the subsequent start.
POSSIBLE CAUSES
1/2 02 SENSOR VOLTAGE LOW
1/2 O2S SIGNAL CIRCUIT SHORT TO GROUND
1/2 O2S SIGNAL CKT SHORT TO GROUND CIRCUIT
1/2 O2 SENSOR DEFECTIVE
PCM DEFECTIVE (1/2 O2S)
TEST ACTION APPLICABILITY
1 Ignition Off
Turn ignition on.
With the DRB, monitor the Downstream O2 Sensor voltage for a few minutes.
Wait three minutes or until the voltage stabilizes (between 0.4 and 0.6 volt).
With the DRB, monitor the Downstream O2 Sensor voltage.
Is the Downstream O2 Sensor voltage below 0.156 volt?All
Ye s®Go To 2
No®The condition required to set this trouble code is not present at
this time.
Perform Powertrain Verification Test VER-5A.
2 Ignition Off
Disconnect the Downstream O2 Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Key on.
With the DRB, monitor the Downstream O2 Sensor voltage.
Is the Downstream O2 Sensor voltage below 0.156 volts?All
Ye s®Go To 3
No®Replace the Downstream O2 Sensor.
Perform Powertrain Verification Test VER-5A.
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Symptom:
P-0139 1/2 O2S SLOW RESPONSE
When Monitored and Set Condition:
P-0139 1/2 O2S SLOW RESPONSE
When Monitored: With the engine running, engine at normal operating temperature,
ambient air temperature greater than þ7ÉC (20ÉF) and vehicle odometer is greater than
6437 Kilometers (4000 miles).
Set Condition: The Oxygen Sensor Signal voltage does not exceed 0.53 volts and does not
fall below 0.35 volts once during the drive cycle.
POSSIBLE CAUSES
ENGINE MECHANICAL PROBLEM
1/2 O2 SENSOR GROUND CKT HIGH RESISTANCE
1/2 O2 SENSOR GROUND CKT POOR CONNECTION
1/2 O2 SENSOR SIGNAL CKT HIGH RESISTANCE
1/2 O2 SENSOR SIGNAL CKT POOR CONNECTION
1/2 O2 SENSOR SLOW RESPONSE
EXHAUST LEAK
1/2 O2S SLOW RESPONSE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1 With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 5
No®Go To 2
2 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Sensor Ground) Circuit between O2S Connector
(Sensor Ground) and PCM Connector (Sensor Ground).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 3
No®Repair poor connection (high resistance) on O2 Sensor Ground
Circuit.
Perform VERIFICATION TEST VER-5A3.
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TEST ACTION APPLICABILITY
3 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Signal) Circuit between O2S Connector (O2S
Signal) and PCM Connector (O2S Signal).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 4
No®Repair poor connection (high resistance) on O2S Signal Circuit.
Perform VERIFICATION TEST VER-5A3.
4 At this time the 1/2 O2S SLOW RESPONSE does not exist or is an intermittent
problem.
With the DRB, read the FREEZE FRAME DATA.
With this screen, attempt to duplicate the condition that has set this fault.
While using FREEZE FRAME DATA pay particular attention to the fault setting
conditions, such as speed, temp, load, and map vacuum.
Does the 1/2 O2S SLOW RESPONSE reoccur?All
Ye s®Go To 5
No®The 1/2 O2S SLOW RESPONSE no longer exists.
Perform VERIFICATION TEST VER-5A3.
5 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Start the Engine.
NOTE: Check the exhaust for excessive smoke caused by oil or coolant
consumption.
Is there an oil or coolant consumption condition present?All
Ye s®Repair engine mechanical as necessary and replace O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Go To 6
6 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Start the Engine.
Check the Exhaust System for leaks between the Engine and the catalyst.
Are there any leaks?All
Ye s®Repair or replace leaking Exhaust System as necessary.
Perform VERIFICATION TEST VER-5A3.
No®Go To 7
7 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Turn Ignition On (Engine Off).
Using a voltmeter, backprobe O2S (Signal) Circuit between O2S Connector (O2S
Signal) and PCM Connector (O2S Signal).
Is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 8
No®Repair poor connection (high resistance) on O2S Signal Circuit.
Perform VERIFICATION TEST VER-5A3.
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DRIVEABILITY
P-0139 1/2 O2S SLOW RESPONSE ÐContinued
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Symptom:
P-0141 1/2 O2S HEATER FAILURE
When Monitored and Set Condition:
P-0141 1/2 O2S HEATER FAILURE
When Monitored: With the ignition key off, after the engine cools down.
Set Condition: No sensor output signal is received when the PCM powers up the sensor
heater.
POSSIBLE CAUSES
1/2 O2 SENSOR CONNECTOR DAMAGED
1/2 O2 SENSOR GND CIRCUIT OPEN
ASD RELAY OUTPUT CIRCUIT OPEN
1/2 O2 SENSOR FAILURE
1/2 O2 SENSOR HEATER ELEMENT FAILURE
1/2 O2S HEATER FAILURE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1 With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 2
No®Go To 3
2 Turn Ignition On (Engine Off), wait three minutes.
With the DRB, monitor the O2 Sensor voltage for a few minutes until the voltage
stabilizes between .4 and .6 volts.
With the DRB, actuate the O2 Heater test.
Monitor O2 voltage for up to two minutes.
Is the O2 Sensor voltage still between .4 and .6 volts?All
Ye s®Go To 3
No®Go To 4
3 At this time the 1/2 O2S HEATER FAILURE does not exist or is an intermittent
problem.
With the DRB, read the FREEZE FRAME DATA.
With this screen, attempt to duplicate the condition that has set this fault.
While using FREEZE FRAME DATA pay particular attention to the fault setting
conditions, such as speed, temp, load, and map vacuum.
Does the 1/2 O2S HEATER FAILURE reoccur?All
Ye s®Go To 4
No®1/2 O2S Heater failure no longer exists.
Perform VERIFICATION TEST VER-5A3.
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TEST ACTION APPLICABILITY
3 Cycle the ignition off, then on.
Attempt to start engine.
With the DRB in Input/Output display, read the current CMP and CKP states.
Did only the CKP state change?All
Ye s®Refer to symptom P-0340 NO CAM SIGNAL AT PCM in the
DRIVEABILITY category.
No®Go To 4
4 Start the engine.
Wiggle the Wiring Harness from CMP and CKP Sensors to the Powertrain Control
Module.
Did the engine miss or die out when wiggling Wires?All
Ye s®Repair Circuit as necessary where wiggling caused the engine to
miss or die out.
Perform Powertrain Verification Test VER-2A.
No®Go To 5
5 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-2A.
No®Test Complete.
6 Ignition Off
Disconnect the Crank Position (CKP) Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Turn ignition on.
Using a voltmeter, measure voltage from the 8-Volt Supply Circuit.
Is the voltage above 7.0 volts?All
Ye s®Go To 7
No®Go To 15
7 Ignition Off
Disconnect the Crank Position (CKP) Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the Sensor Ground Circuit for resistance from the CKP
Sensor Connector to a good ground.
Is the resistance below 5.0 ohms?All
Ye s®Go To 8
No®Repair the open Sensor Ground Circuit.
Perform Powertrain Verification Test VER-2A.
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DRIVEABILITY
P-0320 NO CRANK REFERENCE SIGNAL AT PCM ÐContinued
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